Four small research oil spills (3.54 cu m each) were made to compare the physical and chemical behavior of crude oils on the sea with and without dispersant treatment. Work was performed 90 km southeast of New York Harbor under a research ocean dumping permit from the U.S. Environmental Protection Agency (EPA). Each spill was made from a research vessel and was tracked by vessel and aircraft for several hrs. Two crude oils were used; one spill of each was treated with dispersant after 30 min, and one was allowed to weather naturally as an experimental control. A self-mix dispersant was sprayed on the two treated slicks from a helicopter that had been fitted with a spray system delivering droplets whose mean diameter was approximately 2 mm. More than 750 samples of background water, water under the slicks, and surface water were taken for chemical analysis. Sampling continued for 6 to 7 hr after each spill. Aerial photographs were taken, and representative photographs are presented in this report. Currents and winds were measured, leading to interpretation of physical transport of the oils. This report complements earlier work performed in 1975 and 1978.

Caption title. "March 1984." "EPA-600/2-84-067." Microfiche.